But insiders worry that the hangers-on who enabled and facilitated her fall off the wagon may make their way back into the star’s inner circle.

Since news broke that the singer, 25, had OD’d, fans have been speculating on social media about who might have been a negative influence on the pop star. Lovato had allegedly been partying for 12 hours straight before overdosing. (She reportedly refused to reveal to paramedics what drugs she had taken.)

Narcan is used to stop the effects of opioids (including heroin, oxycodone and fentanyl) and can be administered intravenously, injected into muscle or sprayed up the nose.

It was reportedly used by paramedics after Lovato’s bodyguard found her unconscious at home. TMZ reported that Lovato’s bodyguard administered first aid and propped up the star to clear her ­airway.

“There’s a crew of people in Hollywood [that], when you want to party, you find yourself hanging out with these hanger-on friends and they lead you into [the party life] more and it’s a downward spiral,” said a music producer who has worked with talent including Selena Gomez, a longtime friend of Lovato’s.

“Demi was very vulner­able.”

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An assistant reportedly found Lovato unconscious and unresponsive in her...

Lovato has been open about her struggles for years — candidly discussing her drug and alcohol addictions, bipolar diagnosis, and cutting. In a 2013 interview, she said she used to sneak drugs onto jet flights and couldn’t go 30 minutes without cocaine. In 2017 she revealed that she first used coke at age 17 while working on Disney Channel projects.

“You couldn’t have anything near her. She had to be out of the building or miles away for anyone to be drinking anything,” said the insider.

Heather Jo Clark, who trained Lovato last year at Unbreakable Performance in Los Angeles where Lovato boxed and did martial arts, told The Post that nutritionist Dan Leith lived with the star and would accompany her to the gym to help choose post-workout snacks.

A music source close to Lovato’s former manager, Phil McIntyre, said McIntyre had a strict policy with the troubled star: “He would only manage her if she was being healthy and getting help.”

Sarodj Bertin, an actress who works out with Lovato and has been to five of the singer’s house parties, said ­“everyone who wanted to drink something had to bring their own. She was very serious about” not keeping alcohol at her home.

Despite the seemingly impenetrable wall put up around Lovato, the substances — and the seedy people — sneaked in. TMZ reported that Lovato looked “way out of it” during a French Montana party held during the Coachella music festival in April.

The music producer’s friend, a studio engineer who recently toured with Lovato, told him that Lovato was “fully off the rails” four weeks ago. “He said she was a train wreck and . . . looked like she had been out drinking every night. She just wasn’t fully there.”

According to a Hollywood publicist, two weeks before she overdosed, Lovato hosted a party at her house where she openly indulged in alcohol.

“It was a game night,” said the publicist. “My friend was there and said [Lovato] had two glasses of wine.”

In June, Lovato released her single “Sober,” revealing that she had relapsed, singing: “Momma, I’m so sorry, I’m not sober anymore/And daddy, please forgive me for the drinks spilled on the floor.”

Weeks later, Lovato and McIntyre parted ways, and she dumped her sober coach, Mike Bayer. Days before she OD’d, Lovato forgot the lyrics to ­“Sober” during a concert at the California Mid-State Fair in Paso Robles.

On Friday, TMZ reported that Lovato has agreed to enter in-patient rehab as soon as she is discharged from Cedars-­Sinai Medical Center in LA.

But sources say that while Lovato’s health may be on the mend, her career may be trickier to rehabilitate. “I would definitely be very, very skeptical of working with her without knowing that she was clean and committed to being clean,” said the music source.

“There’s a difference between the public Demi and the private Demi, as open as the public persona seems to be,” added a media insider. “And I think people are now realizing that.”